A braking stand of this kind for metal or sheet metal strips is known from EP-PS 195 096. With this stand, whose chain systems clamp the strip or sheet with carriage-like roller units guided on rails in a straight drag-applying or entraining zone, the large pulling or restraining force (up to 200 t) required when holding back or pulling forward metal strips can be applied without harmful effects to the surface of the strip, which may or may not be divided into narrower strips. This is achieved primarily by controlled feeding of the chain systems with the roller units into a relatively short clamping and entraining zone by means of straight guide rails which simultaneously provide resistance to the large clamping forces. This enables the relatively large clamping forces which are necessary to provide large pulling or restraining forces to be accepted without relative movement between the strip and the circulating, carriage-like roller units. Guiding each chain along a path that is curved except in the entraining zone assists the controlled feeding of the roller units. Thus the chains, which are composed of a plurality of roller units directly coupled together, can move to the greatest possible extent without sudden changes in direction, so that on the one hand the controlled parallel feeding of the opposed roller units of the chain systems into the entraining zone is promoted and on the other hand very high speeds--for example up to 1,000 m/min.--are possible.
With a braking stand of this kind, which enables large pulling or holding forces to be applied without damaging the surface, even strips having very sensitive surfaces, e.g. aluminium strips, can be handled using the desired large pulling or holding forces. It has however been found that, since a closed surface of the roller units only exists in the straight entraining zone, materials such as scale (e.g. if the braking stand is arranged after a furnace), sometimes unavoidable zinc and tin fines, etc. find their way into the chain case through the gaps between neighbouring roller units. Once such pieces, or dirt particles, have entered the chain case, which is located inside the circulating chains, they can accumulate there on the rails, gear wheels and bearings and lead to breakdowns.